diff --git a/src/compiler/program.ts b/src/compiler/program.ts
index 394dc2a7669..bca10eceb67 100755
--- a/src/compiler/program.ts
+++ b/src/compiler/program.ts
@@ -1105,8 +1105,8 @@ namespace ts {
                return equateStrings(file.fileName, getDefaultLibraryFileName(), /*ignoreCase*/ !host.useCaseSensitiveFileNames());
             }
             else {
-                const stringEqualityComparer = host.useCaseSensitiveFileNames() ? equateStringsCaseSensitive : equateStringsCaseInsensitive;
-                return forEach(options.lib, libFileName => stringEqualityComparer(file.fileName, combinePaths(defaultLibraryPath, libFileName)));
+                const equalityComparer = host.useCaseSensitiveFileNames() ? equateStringsCaseSensitive : equateStringsCaseInsensitive;
+                return forEach(options.lib, libFileName => equalityComparer(file.fileName, combinePaths(defaultLibraryPath, libFileName)));
             }
         }